The practice of restorative dentistry and treatment of the associated structures of the dentition and jaws has evolved such that the analysis of the temporomandibular joints is generally not a part of routine dentistry. The issues surrounding centric occlusion, centric relation or the position of maximum intercuspation, are typically managed intuitively by dental practitioners.
Physical registrations at various positions of occlusion are sometimes used to provide additional information about the interocclusal relationships, especially when the practitioner is undertaking prosthodontic and restorative procedures. These are typically made by having the patient close their jaws together on some type of registration material such as wax or polysiloxane. Dental casts are typically mounted with this registration on an articulator and used to simulate the static relationship of the jaw in occlusion. The registration of centric occlusion is often used to describe the position at which the teeth come together and used in context with treatment to the dentition, especially the position of maximum intercuspation, however these measurements typically do not allow for routine analysis of the temporomandibular joints.
In practice, occlusal aspects of restorations may be fitted by trial and error on the model and adjusted in size and shape as needed until a satisfactory size and shape are attained. Mechanical articulators include an upper member and a lower member that are connected together by a pair of pivotal couplings (such as ball and socket joints). The model of the upper arch is connected to the upper member of the articulator, while the model of the lower arch is connected to the lower member of the articulator. In general, the couplings enable the two models to move toward and away from each other but cannot accurately mimic the certain movements of the patient's jaws.
As can be appreciated, however, the technique of articulation that is described above is time consuming and must be carefully executed to ensure that the resulting articulation properly records a useful relationship of the patient's occlusion.
Therefore there is a need for improved methods for measuring maxillo mandibular relationships and relating this information to a treatment plan.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.